$1)$ modify the python functions developed during week $4$ and $5$ to compute the derivatives of the SIR and Lotka$-$Volterra models to make them more "abstract" $($i$.$e$.$ use numpy arrays as input and output$)$; $2)$ rewrite the Euler step function in a way that accepts state vectors and derivative vectors $($gradient$)$ of any dimension by using numpy arrays; $3)$ define a dictionary to contain all the model specific parameters $($i$.$e$.$ r$,$ alpha, beta, and d for Lotka$-$Volterra, k and m for the harmonic oscillator$)$ and pass the dictionary to to the functions that require these values; $4)$ define a new function to set the values of the parameters and the initial conditions $($there will be a specific function for each different model$)$